﻿
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace WebApplicationFileSys.Models
{
    public class SF
    {
        private static volatile ChartApp _db;
        private static readonly object lockObj = new object();


        public static ChartApp db
        {
            get
            {
                if (_db == null)
                {
                    lock (lockObj)
                    {
                        if (_db == null)
                        {
                            _db = new ChartApp();
                        }

                    }
                }

                return _db;
            }
        }

    }
}
